Gemini2544 Posted December 11, 2019 Share Posted December 11, 2019 I have an old Bally MPU board and was wondering If I supplied the 5vdc & 11.9vdc ( dual supply) would it fully boot to 7 flashes on the table not using a test bed or machine? Link to comment Share on other sites More sharing options...
0 Administrators Arcade King Posted December 11, 2019 Administrators Share Posted December 11, 2019 You'll only get 6. Link to comment Share on other sites More sharing options...
0 Gemini2544 Posted December 11, 2019 Author Share Posted December 11, 2019 You'll only get 6. I'm getting 1 pulse a pause then 5 so is that the six? Link to comment Share on other sites More sharing options...
0 Autosteve Posted December 11, 2019 Share Posted December 11, 2019 I'm getting 1 pulse a pause then 5 so is that the six? Yep Link to comment Share on other sites More sharing options...
0 ocyen Posted December 11, 2019 Share Posted December 11, 2019 For the last flash you need solenoid voltage (43v). But according to Pinwiki: For bench testing, it is possible to "trick" The MPU into completing the 7th flash without applying the solenoid voltage by temporarily jumpering the top of R17 and the top of R23. Link to comment Share on other sites More sharing options...
0 Rich Posted December 11, 2019 Share Posted December 11, 2019 Yep No, one pulse and 5 is 5 flashes. On a working Bally MPU board, on start up you should see a flicker then 7 flashes. As mentioned as you are testing on a workbench you won't get the 7th flash, but should get flicker then 6. No 6th flash is U11 and/or U12 bad......or the sockets if not soldered directly to the board. Link to comment Share on other sites More sharing options...
0 Boots Posted December 11, 2019 Share Posted December 11, 2019 If by pulse you mean a quick flicker then agree with rich you have 5 flashes Link to comment Share on other sites More sharing options...
0 Gemini2544 Posted December 12, 2019 Author Share Posted December 12, 2019 I'm getting 1 half second flash a pause for 1 second then 5 flashes then nothing. I would not call the first flash a flicker. Link to comment Share on other sites More sharing options...
0 Autosteve Posted December 12, 2019 Share Posted December 12, 2019 I'm getting 1 half second flash a pause for 1 second then 5 flashes then nothing. I would not call the first flash a flicker. I have found the flicker/ flash combo can change quite a lot between machines. Let's just say the LED needs to go on and off 7 times total and even after 7 times it can still fail to boot correctly. There are also parts of the board that are not tested and problems can show themselves even after a successful LED test. Link to comment Share on other sites More sharing options...
0 Rich Posted December 12, 2019 Share Posted December 12, 2019 In short, Regardless of adjectives used, the LED on the board needs to go on and off 8 times in total. Easiest to see the initial flicker then 7 flashes in the dark. The flicker is the reset section (bottom left of board) working communicating with the processor U9 6800 and U6 rom start up code along with U11. then there are 7 flashes 1st flash - roms are good 2nd flash - U7 6810 is good 3rd flash - U8 5101 ram is good 4th flash -U10 6820/6821 is good 5th flash - U11 6820/6821 is good 6th flash - U11 & U12 555 timer is good 7th flash - CPU tests are done and all good with 43 VDC present then it goes dim and stays that way whilst game is on. Link to comment Share on other sites More sharing options...
0 Gemini2544 Posted December 14, 2019 Author Share Posted December 14, 2019 In short, Regardless of adjectives used, the LED on the board needs to go on and off 8 times in total. Easiest to see the initial flicker then 7 flashes in the dark. The flicker is the reset section (bottom left of board) working communicating with the processor U9 6800 and U6 rom start up code along with U11. then there are 7 flashes 1st flash - roms are good 2nd flash - U7 6810 is good 3rd flash - U8 5101 ram is good 4th flash -U10 6820/6821 is good 5th flash - U11 6820/6821 is good 6th flash - U11 & U12 555 timer is good 7th flash - CPU tests are done and all good with 43 VDC present then it goes dim and stays that way whilst game is on. Well then that suggest the board is working, I just need a new project and Bally or Stern SS to put it in. Link to comment Share on other sites More sharing options...
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